Investigation of the Roughness Effects of Heat Transfer Surface in the Pool Boiling in Acetone-Isopropanol Solution

In this laboratory study, the effect of increasing the surface roughness of heat transfer surface on the heat transfer coefficient in the pool boiling was investigated in two-part solutions of acetone and isopropanol with constant volume percent (% 30 acetone and% 70 isopropanol as well as solution of 70% acetone and 30% isopropanol). The experimental set up consists of an insulated glass cube, a bronze metal cylinder as a heat transfer surface, a pencil light bulb connected to auto transformer as a thermal source. The tests were carried out with four different roughness of the heat transfer surface. The range of heat fluxes is from 5.1 to 88 kW/m2 and in atmospheric conditions. The results show that by increasing roughness, the surface of the bubble production in the solution is increased, which leads to promote of mixing and, consequently, increase in the heat transfer coefficient. The optimal model with maximum overlapping with the experimental results revealed that the Vinayak model with a mean error of 15% has the least error, and Tome model with a mean error of 27% has the most error among other models.